Lightning Behaviour during the COVID-19 Pandemic

Background COVID-19 has drastically dampened human activities since early 2020. Studies have shown that this has resulted in changes in air temperature and humidity. Since lightning activities are dependent on air temperature and humidity, this study is conducted to evaluate the correlation between the intensity of lightning activities with the atmospheric changes, and investigates the changes, in lightning activities due to atmospheric changes during the COVID-19 pandemic. Methods The hypothesis was tested through a t-test and Pearson’s correlation study. The variation trend of lightning strikes count (LSC) in Europe and Oceania during the five months COVID-19 lockdown period (March – July) compared to the same period in the previous five years from 2015 to 2019 is investigated. Results Statistical analysis shows the LSC in Europe and Oceania during the lockdown period dropped significantly by more than 50% and 44% respectively compared to the same period in previous five years. Furthermore, LSC was found to be positively correlated with air temperature and relative humidity in Europe. However, in Oceania, LSC seems to be only positively correlated with air temperature but negatively correlated with relative humidity. Conclusions This study seems to suggest that lightning activities have significantly changed during this pandemic due to reduction in human activities.

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Lightning Behaviour during the COVID-19 Pandemic

F1000Research ◽

10.12688/f1000research.70650.1 ◽

2021 ◽

Vol 10 ◽

pp. 906

Author(s):

Fazandra Yusfiandika ◽

Chun Lim Siow ◽

Chandima Gomes ◽

Aravind Chockalingam ◽

Lee Cheng Pay

Keyword(s):

Statistical Analysis ◽

Relative Humidity ◽

Air Temperature ◽

Human Activities ◽

Correlation Study ◽

T Test ◽

Lightning Strikes ◽

Variation Trend ◽

Temperature And Humidity ◽

Atmospheric Changes

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INFLUENCE OF TEMPERATURE AND HUMIDITY ON THE EMERGENCE BEHAVIOUR OF ANAX JUNIUS (ODONATA: AESHNIDAE)

The Canadian Entomologist ◽

10.4039/ent105975-7 ◽

1973 ◽

Vol 105 (7) ◽

pp. 975-984 ◽

Cited By ~ 10

Author(s):

Robert Trottier

Keyword(s):

Relative Humidity ◽

Water Temperature ◽

Air Temperature ◽

Water Surface ◽

Average Speed ◽

Anax Junius ◽

Air Temperatures ◽

Stage 4 ◽

Temperature And Humidity ◽

Three Stages

AbstractEmergence from the water of Anax junius Drury normally occurred after sunset. The onset was affected independently by water temperature and air temperature; low water temperature and high air temperature delayed the onset of emergence. In the field, the net vrtical distance travelled above the water, before ecdysis, was positively correlated with air temperature. In the laboratory, the vertical distance travelled above the water was greatest when air and water temperatures were approximately the same. The average speed of climbing to the first resting position above the water surface was faster at high than low water temperature, but the average speed of climbing from there to the final position, where ecdysis occurred, was reduced due to the effects of air temperature and humidity. Air temperatures below 12.6 °C were found to retard ecdysis and larvae returned to the water and emerged early the following day making the final process of emergence and ecdysis diurnal instead of nocturnal. The duration of ecdysis was shorter at high than low air temperatures and only the first three stages, as arbitrarily defined, were longer at low than high relative humidity; stage 4, shortened with low relative humidity. This study shows that A. Junius, emerging from the water is affected at first by the temperature experienced when submerged, but it becomes gradually and cumulatively affected by air temperature and humidity while climbing to the ecdysial position and moulting.

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Quantifying the impact of heat on human physical work capacity; part II: the observed interaction of air velocity with temperature, humidity, sweat rate, and clothing is not captured by most heat stress indices

International Journal of Biometeorology ◽

10.1007/s00484-021-02212-y ◽

2021 ◽

Author(s):

Josh Foster ◽

James W. Smallcombe ◽

Simon Hodder ◽

Ollie Jay ◽

Andreas D. Flouris ◽

...

Keyword(s):

Relative Humidity ◽

Empirical Study ◽

Air Temperature ◽

Physical Work ◽

Climate Index ◽

Physical Work Capacity ◽

Air Movement ◽

Wide Range ◽

Temperature And Humidity ◽

The Impact

Abstract Increasing air movement can alleviate or exacerbate occupational heat strain, but the impact is not well defined across a wide range of hot environments, with different clothing levels. Therefore, we combined a large empirical study with a physical model of human heat transfer to determine the climates where increased air movement (with electric fans) provides effective body cooling. The model allowed us to generate practical advice using a high-resolution matrix of temperature and humidity. The empirical study involved a total of 300 1-h work trials in a variety of environments (35, 40, 45, and 50 °C, with 20 up to 80% relative humidity) with and without simulated wind (3.5 vs 0.2 m∙s−1), and wearing either minimal clothing or a full body work coverall. Our data provides compelling evidence that the impact of fans is strongly determined by air temperature and humidity. When air temperature is ≥ 35 °C, fans are ineffective and potentially harmful when relative humidity is below 50%. Our simulated data also show the climates where high wind/fans are beneficial or harmful, considering heat acclimation, age, and wind speed. Using unified weather indices, the impact of air movement is well captured by the universal thermal climate index, but not by wet-bulb globe temperature and aspirated wet-bulb temperature. Overall, the data from this study can inform new guidance for major public and occupational health agencies, potentially maintaining health and productivity in a warming climate.

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Temporal and Spatial Patterns of Temperature and Humidity in Taxodium distichum Shelterbelts of Jiangmen, South China

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.610-613.1150 ◽

2012 ◽

Vol 610-613 ◽

pp. 1150-1154 ◽

Cited By ~ 1

Author(s):

Lu Zhang ◽

Zhi Yao Su ◽

Xiang Lin Wang

Keyword(s):

Relative Humidity ◽

Spatial Patterns ◽

Air Temperature ◽

Seasonal Pattern ◽

Taxodium Distichum ◽

Blank Field ◽

Sugarcane Field ◽

Temporal And Spatial Patterns ◽

Temperature And Humidity ◽

Temporal And Spatial

Temporal and spatial patterns of temperature and humidity in shelterbelts of Taxodium distichum were investigated using routine observation and gradient observation methods in sampling plots placed in Taxodium distichum shelterbelts, sugarcane, and open (blank) fields, respectively. The results showed that: 1) Taxodium distichum shelterbelts mitigated air temperature in July. Air temperature of Taxodium distichum shelterbelts was 0.7 °C and 1.7 °C lower than that of sugarcane field and blank field in July, respectively, while less change of air temperature in January was recorded. Air temperature at 20 cm from the ground in the Taxodium distichum shelterbelts was the highest in April, October and January, but the lowest in July; 2) Relative humidity in the Taxodium distichum shelterbelts was higher than in blank field through the four seasons, but lower than in sugarcane field in July, October and January. Relative humidity in sugarcane field and Taxodium distichum shelterbelts was higher near the ground, and relative humidity in sugarcane field increased significantly; 3) One-way ANOVA followed by Tukey’s HSD indicated that both air temperature and relative humidity were significantly different with a seasonal pattern among shelterbelts of Taxodium distichum, sugarcane field and open field (P＜0.001).

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Effect of Lockdown,Temperature,and Humidity on the Pattern of COVID-19 in Erbil Province,Kurdistan Region, Iraq

Diyala Journal of Medicine ◽

10.26505/djm.20025821123 ◽

2021 ◽

Vol 20 (2) ◽

pp. 56-67

Author(s):

Rundk Hwaiz ◽

◽

Katan Ali ◽

Namir Al-Tawil

Keyword(s):

Relative Humidity ◽

Air Temperature ◽

Death Rate ◽

Weather Conditions ◽

World Health ◽

The Novel ◽

Number Of Patients ◽

Temperature And Humidity ◽

Novel Coronavirus ◽

Health Organization

Background: COVID-19 was first reported in Erbil province in Iraq on March 19, 2020. The effect of lockdown on reducing the spread of the novel coronavirus and the effect of weather conditions (air temperature and humidity) on the daily reported number of cases and death rate of COVID-19 were investigated during April to July, 2020. Objective: To investigate the effect of lock down on reducing the spread of the novel coronavirus pandemic and the effect of weather conditions (air temperature and humidity) on the daily reported number of cases and death rate of COVID-19. Patients and Methods: The data collected during three different periods, the first (total lockdown), followed by the second period of lockdown relaxation, which was followed by the third period (interrupted relaxation of lockdown) that reported hundreds of new cases daily. The real-time PCR .assay was performed on suspected COVID-19 patients according to the protocol established by the World Health Organization. Results: Temperature and relative humidity were recorded in Erbil city in Iraq. Patients’ age ranged (2-70) years old. Out of (1469) patients confirmed positive with COVID-19, 57.7% of them were males, 31.3% were females, and the rest (11%) were children. The mean number of patients per day was 32.77 during the period of interrupted relaxation lockdown which was significantly higher than in the total-lock down period (3.88 patient), and the relaxation lockdown period (1.93 patient). The mortality rate per day was 0.77 during the period of interrupted relaxation lockdown was significantly higher than the rates (0.0%) of the other periods. Moreover, increasing the temperature increased the number of confirmed cases in July while, low relative humidity significantly increased the rate of reported cases. Conclusion: The increase in the number of reported cases of COVID-19, might be related to the interruption of lockdown. Moreover, the daily reported cases and mortality rates increased by increasing the temperature from April to June.

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Influence of Air Temperature and Humidity on Dehydration Equilibria and Kinetics of Theophylline

Journal of Pharmaceutics ◽

10.1155/2013/892632 ◽

2013 ◽

Vol 2013 ◽

pp. 1-9 ◽

Cited By ~ 2

Author(s):

Amira Touil ◽

Roman Peczalski ◽

Souad Timoumi ◽

Fethi Zagrouba

Keyword(s):

Relative Humidity ◽

Air Temperature ◽

Solid Phase ◽

Gravimetric Analysis ◽

Dehydration Rate ◽

Processing Times ◽

Theophylline Monohydrate ◽

Temperature And Humidity ◽

Polymorphic Forms ◽

Kinetics Of

The effect of hygrothermal conditions (air temperature and relative humidity) on the dehydration of theophylline monohydrate was investigated. Firstly, the equilibrium states of theophylline were investigated. The data from gravimetric analysis at constant temperature and humidity were reported as desorption isotherms. The PXRD analysis was used to identify the different polymorphic forms of theophylline: the monohydrate, the metastable anhydrate, and the stable anhydrate. Solid-solid phase diagrams for two processing times were proposed. Secondly, the dehydration kinetics were studied. The water content evolutions with time were recorded at several temperatures from 20°C to 80°C and several relative humidities from 4% to 50%. Different mathematical models were used to fit the experimental data. The spatially averaged solution of 2D Fickian transient diffusion equation best represented the water mass loss versus time experimental relationship. The dehydration rate constant was found to increase exponentially with air temperature and to decrease exponentially with air relative humidity.

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The Effect of Drying Air Temperature and Humidity on the Drying Kinetic of Kenaf Core

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.315.710 ◽

2013 ◽

Vol 315 ◽

pp. 710-714 ◽

Cited By ~ 8

Author(s):

Suhaimi Misha ◽

Ali Sohif Mat ◽

Mohd Hafidz Ruslan ◽

Kamaruzzaman Sopian ◽

Elias Salleh

Keyword(s):

Relative Humidity ◽

Air Temperature ◽

Coefficient Of Determination ◽

Suitable Model ◽

Chi Square ◽

Experimental Conditions ◽

Kenaf Core ◽

Thin Layer Drying ◽

Drying Kinetic ◽

Temperature And Humidity

Drying kinetics of kenaf core was investigated in a Low Temperature and Humidity Chamber Test. The drying experiments were carried out at temperature of 45, 50 and 55°C and air relative humidity of 10, 20 and 30% using a constant air velocity of 1.0 m/s. The moisture content data at various drying air conditions were converted to moisture ratio and plotted against time to obtain the drying curves for each experimental data. The curves were fitted to eight different thin layer drying models to determine a suitable model for drying of kenaf core. The fit quality of the models was evaluated based on their coefficient of determination (R2), reduced chi-square (χ2) and root mean square error (RMSE). Among the eight models, Two Term model is the best model for describing the drying behavior of kenaf core. The drying air temperature gave more significant effect on the drying kinetic of kenaf core compared to the drying air relative humidity under the experimental conditions studied.

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Temporal simulation of diurnal temperature and relative humidity evolution at a forested mountainous site in Attica, Greece

International Journal of Wildland Fire ◽

10.1071/wf02019 ◽

2002 ◽

Vol 11 (2) ◽

pp. 95 ◽

Cited By ~ 3

Author(s):

Haralambos Feidas ◽

Constantinos Cartalis ◽

Constantinos Lagouvardos

Keyword(s):

Relative Humidity ◽

Air Temperature ◽

Weather Conditions ◽

Diurnal Temperature ◽

Area Of Interest ◽

Daily Cycles ◽

Temperature And Humidity ◽

Weather Changes ◽

Definition Of ◽

June July

Knowledge of the prevailing weather conditions regarding air temperature and humidity is critical for the definition of the Fire Weather and Fire Danger indices. In this study, two fitting algorithms were developed for the simulation of the diurnal air temperature and relative humidity cycles, using 2-hourly measurements at the forested site of Mount Parnes in Attica, Greece. Both algorithms use as input values the observed daily minimum and maximum values of air temperature and humidity to simulate the temperature and relative humidity daily cycles, respectively. In general, the algorithms provide satisfactory results especially for the three summer months (June, July and August). A 2-day prediction of the diurnal temperature and humidity cycles was also attempted using as input the temperature or humidity data of the previous days in the area of interest. The prediction may be considered satisfactory for the three summer months and less satisfactory for May and September due to weather instability. Finally a dynamic model was also used for supporting the performance of the developed algorithms, especially in the event of sudden weather changes.

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Effects of Air Temperature and Humidity on the Kinetics of Sludge Drying at Low Temperatures

Energies ◽

10.3390/en14227722 ◽

2021 ◽

Vol 14 (22) ◽

pp. 7722

Author(s):

Zhenyu Wang ◽

Lin Xu ◽

Dong Liu ◽

Qing Zhang ◽

Anjie Hu ◽

...

Keyword(s):

Relative Humidity ◽

Air Temperature ◽

Experimental Results ◽

Drying Rate ◽

Maximum Relative Error ◽

Linear Distribution ◽

Thin Layer Drying ◽

Temperature And Humidity ◽

Sludge Drying ◽

The Relationship

In this study, a low-air temperature sludge drying system was constructed and the effects of temperature and relative humidity on the characteristics of the system were investigated. The results showed that the drying rate of sludge increased with an increase in air temperature and a decrease in the air’s relative humidity. The influence of temperature on the average drying rate exhibited an approximate quadratic distribution, while the influence of relative humidity on the average drying rate exhibited an almost linear distribution. The relationship equations of the average drying rate, temperature, and humidity were summarized and compared with the experimental results, and the maximum relative error was 7.6375%. By comparing the experimental results with the commonly used thin-layer drying models, it was found that the sludge drying characteristics were more consistent with the Midilli model. Based on the relevant parameters of the Midilli model, the relationship between the segmented drying moisture content and the average drying rate was proposed, and the empirical formula of the drying rate and MR under different conditions was fitted.

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Enhanced Climate Control of Semi-arid and Arid Greenhouses Equipped with Fogging Systems

10.32747/2012.7593383.bard ◽

2012 ◽

Author(s):

Raphael Linker ◽

Murat Kacira ◽

Avraham Arbel ◽

Gene Giacomelli ◽

Chieri Kubota

Keyword(s):

Relative Humidity ◽

Air Temperature ◽

Natural Ventilation ◽

Agricultural Research ◽

Tracking Error ◽

Climate Control ◽

Cooling Strategy ◽

Temperature And Humidity ◽

New Strategy ◽

Semi Arid

The main objectives were (1) to develop, implement and validate control procedures that would make it possible to maintain year-round air temperature and humidity at levels suitable for crop cultivation in greenhouses operating in arid and semi-arid regions and (2) to investigate the influence of the operational flexibility of the fogging system on the performance of the system. With respect to the development of climate controllers, we developed a new control approach according to which ventilation is used to maintain the enthalpy of the greenhouse air and fogging is used to adjust the humidity ratio inside the greenhouse. This approach is suitable mostly for greenhouses equipped with mechanized ventilation, and in which the air exchange rate can be controlled with enough confidence. The development and initial validation of the controllers were performed in a small experimental greenhouses located at the Agricultural Research Organization and very good tracking were obtained for both air temperature and relative humidity (maximum mean deviations over a 10-min period with constant setpoints lower than 2.5oC and 5% relative humidity). The robust design approach used to develop the controllers made it possible to transfer successfully these controllers to a much larger semi-commercial greenhouse located in the much drier Arava region. After only minimal adjustments, which did not require lengthy dedicated experiments, satisfactory tracking of the temperature and humidity was achieved, with standard deviation of the tracking error lower than 1oC and 5% for temperature and relative humidity, respectively. These results should help promote the acceptance of modern techniques for designing greenhouse climate controllers, especially since given the large variety of greenhouse structures (shape, size, crop system), developing high performance site-specific controllers for each greenhouse is not feasible. In parallel to this work, a new cooling control strategy, which considers the contribution of humidification and cooling from the crop, was developed for greenhouses equipped with natural ventilation. Prior to the development of the cooling strategy itself, three evapotranspiration models were compared in terms of accuracy and reliability. The cooling strategy that has been developed controls the amount of fog introduced into the greenhouse as well as the percentage of vent openings based on the desired vapor pressure deficit (VPD) and enthalpy, respectively. Numerical simulations were used to compare the performance of the new strategy with a constant fogging rate strategy based on VPD, and on average, the new strategy saved 36% water and consumed 30% less electric energy. In addition, smaller air temperature and relative humidity fluctuations were achieved when using the new strategy. Finally, it was demonstrated that dynamically varying the fog rate and properly selecting the number of nozzles, yields additional water and electricity savings.

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